Ignition system.



S. C. McKEDWN. IGNITIDN SYSTEM. wrucanou FILED JAN. 29. l9|B 1,292,838. Patented Jan. 28, 1919.

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' IGNITION SYSTEM.

To all whom it may concern:

"Be it lmown that I, Sumner. C. MGKEOWN, a citizen ofthe United States, residing, at East Orange, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Ignition Systems, of which the following is a specification.

' f My invention relates toan ignition system such as used for the purpose of firing the char es in an internal combustion engine.

Within the last few years the rotative speed of the crank shafthas been materially increased so that considerable trouble .has

been experienced in producing ignition apparatus which will satisfactorily fire these high speed engines and which will have a reasonable length of life, since in general it which is used to control the sparks must function with exceeding rapidity and precision and in order to withstand the wear occasioned by such speeds as the above and even lower speeds, special means must be provided 11nd great care exercised in the construction of the parts.

If a high tension magneto be used for 'nition purposes the cam which operates the circuit breaker should, to get the greatest efi'ect from the coil windings, hold the breaker contacts open as long as possible in order to give the coil an opportunity to expend its energy across the spark gap in the engine cylinders to which it is then connected. It is usual to provide means for advancin'g and retarding the time of spark .with reference to the engine pistons and in some caseswhere this range of advance and retard isbonsiderable a. condition may be obtained in the full retard positionsuch that the distributer member may have passed beyond the line of contact in the distribute:- block while the current is still flowing through the secondary winding of the induction coil, which 'may be on the armatureof the magneto or elsewhere, under which condition burning of the insulatin material will ensue in the neighborhood 0% Specification of Letters Patent.

' A lication on new 29, 1am. sci-w No. 214,324.

Patented Jan. 28, 1919.

the distributer contact. In addition to this difficulty the spark may jump from the distributing member to another distributor contact in the direction of rotation of the dis tributing member with consequent detrimental results which will be at once obvious. This latter trouble is apt to be encountered in a distributor that is relatively small in design, necessitated by certain conditions of mounting on the engine, and where a wiping contact brush is used. Such brushes are usually of carbon and many times leave a thin track of carbon (lust around the distributer from contact to contact and if the spark is maintained too long on the cylinder under compression, it may change its direction over the carbon trail to another cylinder where there is no compressionand little resistance to its passage.

It is the primary object of my invention to provide an ignition system in which the 'above difliculties are overcome and in which magneto particularly adapted for firing a two. cylinder internal combustion engine, further reference to the details of which may be found in Patent #1.189,37-i, issued July 4, 1916, to Charles T. Mamn.

Fig. 2 illustrates one position of the main and auxiliary circuit breakers used in my invention.

Fig. 3 shows diagrammatically the position of the distributor parts corresponding to the position of the circuit breaker in Fig. 2, both being used in connection with the machine shown in Fig. 1.

'Figs. 4 and 5 illustrate another position of the distributer parts and circuit breaker from those shown in Figs. 3 and 2.

Fig. 6 shows the distributor turned 180 degrees from Fig. 4 in which the cam of Fig. 5 would be turned 180 degrees corre- Fig. 9 illustrates the distributor parts turned through 180 degrees from that of Fig. 7.

n Figs. 1 to 9 inclusive the breaker mechanism is indicated as fixed, that is, there is no advance or retard shown on the breaker mechanism Fig. 10' illustrates diagrammatically a four cylinder distributor in operative relationship with the breaker mechanism shown in full advance position.

Fig. 11 shows the breaker mechanism in full advance position but the cam in slightly different relation.

Fig. 12 indicates the distributor parts in operative relation with the breaker mechanism in full retarded position.

, Referring now to the details, 1 is a magneto of the type hereinabove referred to hav' ing a distributing member 2 operatively connected with the shaft 3. Distributor contacts 4 and 5 collect the current from distributer 2 and deliver it by means of conductors G and 7 to their respective spark plugs in the engine cylinders. Mounted on the opposite end of the magneto and consequently n at shown in Fig. 1 is a circuit breaker'i'i'ni'c anism shown somewhat diagrammatically in Fig. 2. This breaker mechanism has a stationary contact member 8 carrying an adjustable contact 9. A movable member 10 carries a contact 11 adapted to cooperate with the contact 9. The member 10 is preferably ivoted, as by means of a pivot screw 12, to t ie frame of the breaker box, a spring 13 being used to return the breaker to close the contacts 9' and 11 after the same have been separated by the cam 14. In order to produce a relatively long lifeof the cam 1 k and bumper 15,carried by the movable member 10, the cam lobes 16and17are made relatively long and fiat. If these lobes are made very sharp experience has shown that they would cut the bumper 15 away rapidly, how ever, .where the lobes 16 and 17 are made relatively long and flat difficulty is encountered by the distributor member 2 turning forward in its rotative movement to such a oint that the brush 18, referring to-Fig. 4, leaves the end 19 of the distributing member 2 before the breaker arm 10 has closed the contacts 9 and 11 which, as shown in Fig. 5, control the circuit through the primar P of the induction coil, whose. secondary g is connected to the brush 18 or the additional difiiculty may be encountered of the point 20 of the distributing member 2 advancing so near thecontact 5 that the spark will jump from the end 20 to the contact 5 prematurely. This latter trouble is further aggravated by the track of the brushes on that part of the surface between the ends 19 and 20. which is of insulating material. As shown in Fig. 5 the cam 14 has just separated the contacts 9 and 11 and the current from I coiiperating line the secondary S is passing to (listribu r contact 4. It will be seen that the cam lobe 17 (in Fig. 4) will still be in engagement with the bumper 15 after the brush 18 has left the end 19 of the distributing member 2 and burning of the insulation would follow or the spark might jump from the end 20 to the distributer contact 5 as already pointed out, if means were not provided to prevent this. I rovide such means which are as follows ounted on the stationary contact 8, which is preferably insulated from the breaker box, is a fiexiblemember 21 carrying a bumper 22 and contact 23 which is adapted to coiiperate with a stationary contact '24 which, as diagrammatically shown, is connected to the framework of the breaker box which is usually designated as ground. Referring again to Figs. 4 and 5 it will be seen that the lobe 16 of cam 14 is just coming intocngagement with the bumper 22 and directly thereafter the member 21 is moved to close the contacts 23 and 24 before the brush 18 leaves the end 19 of distributor member 2. Closing of the contacts 23 and 24, as above described, closes the primary circuit of the induction coil and thereby su presses the action of the secondary across t e spark gap so that the troubles'as hereinbefore outlined are removed. When the distributing mem her 2 has turned 180 degrees from that shown in Fig. 4 it will be in the position in Fig. 6. In this position the only difliculty encountered being the tendency of the spark to jump from the point 20 to the contact 4 but the means above described prevents this trouble.

As the cam 14 and the distributing member rotate forward from thepositions shown in Figs. 4 and 5 the auxiliary breaker maintains the contacts 23 and 24 closed until the main circuit breaker itself closes the contacts 9 and 11 as shown in Fig. 8, in which position the distributin member 2 is indicated 'in Fig. 7. From 13% breaker arm 10 prevents any action of the primary on the secondary S until the positions of Figs. 2 and'3 are reached when action takes place as already described.

In Fig. 10 I have shown diagrammatically a distributer block 25 having contacts 2627-28 and 29 coti crating with which is a distributing member 30. The circuit is point on, the circuit tributer has the same corres onding parts as shown in Figs. 2-5 and 8 a though the cam has 4 lobes 31-32-33 and 34. The cam 14 may have any number of lobes required. In Fig. 10 the circuit breaker is indicated in its full advance osition under which condition the relation between the distributing member and the distribuber contacts of the block 25 are as indicated; that is to say, the distributing member 30 has just come into with the distributer contact passes to the distributer contact 26 throughthe distributing member 30 which has advanced isorward but is still in coiiperative relationshlp with the distributer contact 26' hence no trouble will be encountered in fuli advanced position of the breaker box. However, when the breaker box is retarded as indicated in Fig. 12 the cam, which is synchronously timed with the distributer, all

as is well known and understood, must turn in the direction of rotation a niimber of degrees forward before it comes into engagement with the bumper 15 on the circuit breaker arm 10 and, as indicated in Fig. 12, the contacts 9 and 11 are still separated although they are about to close while it is seen that the distributing member 30 has left the line of co6peration35 of the distributer contact 26 and arcin would be produced between the distributin member 30 and the contact 26 but it wil be noted that the auxiliary breaker member 21 has already closed the contacts 23 and 24-thereby suppressingthe current impulses from the secondary winding S.

From what has been said it will be seen that I have aimed to secure long life of the cam and main circuit breaker by constructing these parts so as to give maximum life, yet in so constructing the parts I have encountered certain ignition difiiculties which I have overcome by means of an auxiliary circuit breaker which, in my preferred form, is operated by the same cam that operates the maincircuit breaker. It is evident that the auxiliary breaker may be 0 erated by some other means and that tii relation of the parts of the auxiliary breaker where there is no compression to act against.-

While I have shown what may be termed a service magneto as the source of current for the induction coil itlwill be apparent nected in the same manner as the battery and vibrator to the contact member 8.

When these auxiliary devices are used for starting pur oses the tendency is to run into the trou le heretofore pointed out but since either of the arrangements just mentioned are timed by the main breaker arm 10 and further controlled by the auxiliary breaker 21 the difliculty is overcome. Numerous other changes and alterations may be made in the various details necessary to carry m invention into practical operatidh, and I, therefore, do not wish to be limited to the details herein shown which are more or less diagrammatical in form, and it is intended that the claims shall cover the invention broadly whether or not the current for the induction coil be furnished exclusively by the service magneto itself or whether an auxiliary source be used in connection with the service magneto for the purpose of as sisting in starting.

Having thus described my invention what I claim is 1. In an ignition system, an induction coil having primary and secondary windings with means for producin current in said primary winding, a distri uter having distributer contacts and a distributing member adapted to coiiperateh'ith said contacts connected to the secondary winding, a main circuit breaker for controlling the action of the primary winding on the secondary and an auxiliary breaker for limiting the conprimary for generated in said secondary and an auxiliary reaker adapted to be acted on by said cam. subsequent to the operation of the main breaker for suppressing the action of the primary on the secondary for the purpose 7 described.

3. In an ignition system, an induction coil ,having primary and secondary windin current in said with means for producing] h d uter aving isprimary winding, a distrl that any other suitable" source of energizaftributer contacts and a distributing member tion of the coil ma be utilized, for example,

a battery and vi rator such as shown in Patent #1,207,193, issued December 5, 1916, to Charles T. Mason may be connected to the contact member 8 for the purpose of producing a starting ignition current; or an auxiliary starting. magneto may be conadapted to cooperate with said contacts connected to the secondary winding, a movable member carrying. a contact, a stationary member carrying a contact adapted to cooperate with the movable contact, said contacts being in said primary circuit,,a cam adapted to act on said movable member to &

make'and break said primary circuit whereby current im ulses are generated in said secondary win in a second stationary contact and a movabfi: contact connected to the first mentioned stationary member adapted to be acted on b said cam and to cooperate with'the secon mentioned stationary contact to close said primary circuit after having beenopened by the first mentioned movab e member for the purpose described.

4. In an ignition system, an induction coil having rimary and secondary windings with means or producing current in said primary winding, a distributer having distributer contacts and a distributing member adapted to cotiperate with said contacts connected to the secondary winding, a pivoted movable member carrying a contact, a stationary member carrying an adjustable contact adapted to cotiperate with the movable contact, said contacts being in said primary circuit,'a cam adapted to act on said pivoted member to make and break said primary circuit, whereby current im ulses are generated in said secondary win ing, a second stationary contact, a flexible member attached to the first mentioned stationary contact carrying a contact adapted to cooperate with the second mentioned stationarycontact and further adapted to be acted on by said cam to close after a predetermined interval said primary circuit after it has been opened by said pivoted member, for the purpose described.

In an ignition system, an induction coil having primary and secondary windings with means for producin current in said primary winding, a distri uter having dist-ributer contacts and a distributing'hember adapted to cotiperate with said contacts connected to the secondar winding, a main circuit breaker for pr ucing action of'said primary on said secondary whereby current impulses are sent from said distributing member to said distributer contacts and an auxiliary breaker for suppressing said ourrent impulses before said distributing member passes out of the line of cooperation with said distributor contacts.

6. In an ignition system, an induction coil having primary and secondary windings with means for producin current in said primary winding, a distri mter having distributor contacts and a distributing member adapted to cooperate with said contacts connected to the secondary winding, a main circuit breaker for producing action of said primary on said secondary wherclr current impulses are sent from said distri iuting member to said dist ributer contacts, with means for advancing and retarding said action, a bumperon the movable part of said breaker, a cam adapted to engage said bumper said cam and bumper being so arranged with reference to said distribntcr parts and so constructed for giving maximum life of operation that in full retard position said dis tributing member will pass from the line of cooperation with an associated distributor contact, and means for suppressing said current impulses before the main circuit breaker closes and the distributing member leaves the line of cooperation of the distributer contact.

7. In an ignition system, an induction coil having primary and secondary windings with means for producing'current in sald primary winding, a distributer having distributer contacts and a distributing member adapted to eoiiperate with said contacts connected to the secondary winding, a i i cuit breaker for producing action of said primary on said secondary whereby current impulses are sent from said distributing member to said distribute-r ontacts, a cam for operating said breaker and an auxiliary breaker operated by said cam to close the rimary circuit before the main circuit breakercloses and before the distributing member leaves its cooperating contact for the purpose described.

In witness whereof, I aflix my signature.

SAMUEL C. MCKEOWN. 

